1. Every farm tractor, self-propelled unit of farm equipment, or towed implement of husbandry, manufactured or assembled after January 1, 1980, must at all times, and every farm tractor, self-propelled unit of farm equipment, or towed implement of husbandry must, when operated upon the highways of this state during the times mentioned in section 39-21-01, be equipped as follows:

a.    Tractors and self-propelled units of farm equipment must be equipped with two single-beam or multiple-beam headlamps meeting the requirements of section 39-21-20 or 39-21-22; provided, that a tractor or self-propelled unit of farm     equipment which is not equipped with an electrical system must be equipped with at least one lamp displaying a white light visible when lighted from a distance of not less than one thousand feet [304.8 meters] to the front of the vehicle. Every tractor and self-propelled unit of farm equipment must be equipped with at least one lamp displaying a red light visible when lighted from a distance of one thousand feet [304.8 meters] to the rear of the vehicle. In addition, every tractor and every self-propelled unit of farm equipment must be equipped with two red reflectors visible from all distances from six hundred feet [182.88 meters] to one hundred feet [30.48 meters] to the rear when directly in front of lawful lower beams of headlamps.

b.    Every towed unit of farm equipment or implement of husbandry must be equipped with at least one lamp displaying a red light visible when lighted from a distance of one thousand feet [304.8 meters] to the rear or two red reflectors visible from all distances within six hundred feet [182.88 meters] to one hundred feet [30.48 meters] to the rear when directly in front of lawful lower beams of headlamps. In addition, if the extreme left projection of a towed unit of farm equipment or implement of husbandry extends beyond the extreme left projection of the towing tractor or vehicle, the unit or implement must be equipped with at least one amber lamp or reflector mounted to indicate as nearly as practicable the extreme left projection and visible from all distances within six hundred feet [182.88 meters] to one hundred feet [30.48 meters] to the front when illuminated by the lower beams of headlamps and at least one red lamp or reflector so mounted and visible from the same distances to the rear.

2.    The lamps and reflectors required by this section must be so positioned as to show from front and rear as nearly as practicable the extreme projection of the vehicle carrying them on the side of the roadway used in passing the vehicle. If a farm tractor or a unit of farm equipment, whether self-propelled or towed, is equipped with two or more lamps or reflectors visible from the front or two or more lamps or reflectors visible from the rear, the lamps or reflectors must be so positioned that the extreme projections both to the left and to the right of the vehicle must be indicated as nearly as is practicable. If all other requirements are met, reflective tape or paint may be used in lieu of the reflectors required in subdivision b.